Mind is one of two components of Cartesian dualism, the other being body. Mind is where the soul is supposed to reside and is the non-materialistic, eternal, undetectable ghost in the machine that controls the mindless body. Rene Descartes formulated the concept and even went so far as the label the pineal gland as the point where mind and body intersect.

Dualism as a scientific concept suffers because it is ultimately unfalsifiable. Some proponents follow a God of the gaps style of argument where the non-materialist reality is the cause for whatever materialism can not, at that moment, explain.